FIG. 4(I) shows a known bearing seal for sealing the bearing space of a rolling bearing. This bearing seal comprises a metal core 21 and a rubber seal 31 fixed to the metal core 21.
The metal core 21 comprises a bent portion 22 press-fitted in a seal groove 41 formed in the radially inner surface of an outer race 40 of a bearing at each end portion thereof, a radially outer flange 23 extending radially inwardly from the end of the bent portion 22 located inside of the bearing, a tapered tubular portion 24 having its large-diameter end connected to the small-diameter end of the radially outer flange 23 and its small-diameter end located axially outwardly of its large-diameter end, and a radially inner flange 25 extending radially inwardly from the small-diameter end of the tapered tubular portion 24. The tapered tubular portion 24 is bent at point 24a such that its large-diameter portion 24b located radially outwardly of the bent point 24a has a tapered angle α2 relative to the axis that is larger than the tapered angle β2 of the small-diameter portion 24c located radially inwardly of the bent point 24a. 
The rubber seal 31 is fixed to the inner surface of the metal core 21 facing the interior of the bearing by vulcanization and covers the area of the metal core 21 from the bent portion 22 to an intermediate portion of the radially inner flange 25, and has a thick-walled portion 32 covering the inner surface of the small-diameter portion 24c. Three lips, i.e. an inner lip 33, an intermediate lip 34 and an outer lip 35 are formed on the radially inner surface of the thick-walled portion 32 so as to be axially spaced from each other.
In this bearing seal, with the bent portion 22 press-fitted in the seal groove 41 formed in the radially inner surface of the outer race 40 at its end, the tips of the three lips 33, 34 and 35 of the rubber seal 31 are elastically in contact with the cylindrical radially outer surface 43 of the inner race 42 while bent outwardly of the bearing. Thus, this bearing seal shows extremely high grease sealability, dust-proof properties and waterproofness. Also, the radially inner flange 25 prevents foreign objects having large diameters such as sand from colliding against the outer lip 35, thus preventing damage to the outer lip 35. This improves the durability of the bearing seal.